抄録
21-Hydroxylase, 17α-hydroxylase and C17-20 lyase activites on porcine adrenal microsomes were measured by incubation of radioactive steroids with nicotineamide adenine dinucleotide phosphate. [4-14C]-Progesterone, [4-14C]-pregnenolone, [4-14C]-17α-hydroxyprogesterone and [4-14C]-11-deoxycorticosterone were used as a substrate. 21-Hydroxylase and 17α-hydroxylase activities showed the maximum value in 170 mM and 80 mM potassium phosphate buffer (pH 7.5), respectively. Inhibitory effect of carbon monoxide on 21-hydroxylation and 17α-hydroxylation of progesterone by porcine adrenal microsomes was investigated. The degree of inhibition on two hydroxylation reactions differed. The rate of CO to O2 needed for 50% inhibition of the 21-hydroxylase and 17α-hydroxylase activities were 3.22 and 29.1, respectively.
